simple yes or no answer please

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
Will the gasoline milage improve when I mix it 1/35 instead of 1/20
will the hill climbing get better as well.

Thanks
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
The gas mileage will likely remain the same. So that's a "NO".
The "YES" is it will climb a hill better due to a better/more combustable mixture.

It will get better mileage and climb hills better after it is totally broken in (about 500 miles or so).
 

Norman

LORD VADER Moderator
Jan 16, 2008
2,605
2
38
68
pampa texas
Deacon Yea it might and no I don;t knowrotfl
Come on now how far can you get on an electric before the battries go dead.
Fill that tank up above the seam and go take a good ride, wear it out( or should I say go ride your broom) wink wink.rotfl
Norman:ride2:
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
My wife rides the broom, It pushes me around some, then I push it around some. and sometimes i worry about the heat on the wooden broom handle lol
 

Norman

LORD VADER Moderator
Jan 16, 2008
2,605
2
38
68
pampa texas
Your old lady is going to put that broom where the sun don't shine iffin ya ain't carefull. All you can hope for is she will dip the end in oil first or you will feel a mild bit of discommfert.rotfl
Norman(^)
 

Bikeguy Joe

Godfather of Motorized Bicycles
Jan 8, 2008
11,843
237
63
up north now
But Pablo....hill climbing WILL get better after break-in. Slightly.

I'll add that the vibes will subside somewhat too.
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
3,665
6
38
Duvall, WA PNW
www.sickbikeparts.com
But Pablo....hill climbing WILL get better after break-in. Slightly.

I'll add that the vibes will subside somewhat too.
Agree. I was answering in terms of the mix ratio. And on that subject, let's ignore the break-in factor - If I may read between the lines of the "yes or no" required response.... deacon could be asking: If I don't change my jetting at all and make my pre-mix more oil lean ("1/35 instead of 1/20") will I make more power? Here's some thoughts:

1) By leaning back your oil, you will actually make your air/fuel mixture more fuel rich. Will a more fuel rich mix make more power? Only if your air/fuel mix was too lean before.

2) By leaning back your oil, you may compromise piston ring seal a bit. I have to think these crude 2 -stroke engines need all the ring seal they can get (I could be wrong), but even I, "King of Oil Lean" will not go beyond 40:1. We'll see. Some loose race only engines make most power at less than 20:1.

What about MPG? Again - in a perfect world, if you change the oil mix ratio leaner and nothing else changes, your MPG may even go down a hair.

I'm not sure if you saw this: http://motorbicycling.com/f4/oil-2-cycle-pre-mix-42.html
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
I'm running fine. I forgot some of my problem is a very tight rear wheel assembly from a bike store repair while building the bike. They said it would have to wear in a bit and that is accounting for a lot of my rough running. That is getting better as the bike runs.

I am running the 1/20 break in mix. I was hoping for a little better gas mileage with the 1/35 mix simply because the octane should go up. More combustion with the thinner mix. It is well within the mfg recommendations for the engine.

If there was no difference in the power/mileage, why would there even be two mixes. That was my thinking.

I also run this engine on a 24" wheel. I was told this would make it run slower but climb hills better. It will climb the small hills just fine, but it slows dramatically on larger ones. Even to the point I need to pedal. That surprised me some. Again that tight rear wheel comes into play some there as well. I note that I have to be very careful or I accidentally apply some brake. Coaster brakes you know. I think the bike shop set them tight and I just have to wear it down now.

Thanks for the info though.
 

paul

Well-Known Member
Dec 23, 2007
5,548
39
48
63
Kalamazoo, MI
i think part of it is your engine is not broken in yet. you will know when it is. i always heard this on cars and motorcycles but never noticed any difference. on these little 2 stroke engine you will notice a big difference. don't be in a big hurry to change your oil fuel mixture. stick with the recommended is my advice.
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
3,665
6
38
Duvall, WA PNW
www.sickbikeparts.com
I am running the 1/20 break in mix. I was hoping for a little better gas mileage with the 1/35 mix simply because the octane should go up. More combustion with the thinner mix. It is well within the mfg recommendations for the engine.

If there was no difference in the power/mileage, why would there even be two mixes. That was my thinking.
Being an (ex) turbo car guy I used to believe that oil in gas kills the octane, big time - and it IS true for 4-stroke engines, especially with regular (crankcase) motor oil. But 2-stroke engines and 2-stroke oil, not so much. Some of the oil does combust, but a good oil drops out of the vapor mix very near the top of the compression stroke, to seal and lubricate.

I think the two given ratios are a bit of a red herring - I can see some extra lube for break in, but...........
 

Pablo

Master Bike Builder & Forum Sponsor
Dec 28, 2007
3,665
6
38
Duvall, WA PNW
www.sickbikeparts.com
i think part of it is your engine is not broken in yet. you will know when it is. i always heard this on cars and motorcycles but never noticed any difference. on these little 2 stroke engine you will notice a big difference. don't be in a big hurry to change your oil fuel mixture. stick with the recommended is my advice.
Wow - such juicy topics for the morning! On all the stroke engines I have owned over the years, I never monkeyed with the mix for break-in and after break-in. Indeed these bike engines look pretty crude and I suppose the extra oil is to help carry away the high/rough areas (asperites) as they wear away. BUT here are my controversial comment:

1) I am a fairly strong believer in not babying an engine for break in. I think too much easy engine action, early, delays break-in and may even glaze the cylinder.

2) Too much oil, may not hurt anything (except make it run fuel lean), but a cheap oil may gum the rings up a bit, too.

I will run mine a bit oil rich for the first tank or two, and yeah I'll go a bit slow as I learn it and proof test the bike and engine. But after a bit I'll be going hard! I can be your guinea pig!!:crash:
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
Thanks guys, I have run about 60 oz of oil rich fuel through and plan to run about 40 more before I switch it. Then I'm going to go 1/32 purely for convenience of mixing. One ounce in a 32 ounce plastic bottle then fill with gas. That should be a safe enough mix and easy to do in a hurry. Get rid of the gas beaker I am using now to measure out twenty ounces of gas.

I don't really baby the engine. I ride it about 3/4 throttle on the flats and downhill and wide open going uphill. On my test track it is about 25% up hill so it works out I hope about right.

I'm going to start running it a little farther and harder next nice day. I have been doing under five miles at a clip. I'm going to go for about ten next time.

Yes Norman with more gas in the tank this time.
 

paul

Well-Known Member
Dec 23, 2007
5,548
39
48
63
Kalamazoo, MI
i didn't go easy during break in either but i had heavy oil mix. what i am saying is when these engines break in their is a big time noticeable change in power. first engine i ever had that their was a noticeable difference
 

deacon

minor bike philosopher
Jan 15, 2008
8,117
3
0
north carolina
I await it with bated breath. When the wheel loosens up it will also help i expect. That's what is causing the uneven drive I'm sure.